Cisco Analog Voice Network Interface Module is a digital card that supports multiple voice applications on theISR 4000 routers. This system is provided with an on-board digital signal processor and there is no requirement of Packet Voice DSP module for router on motherboard. It has a high speed WAN interface card which increases the port density and module capability.Cisco Analog Voice Network Interface Moduleincludes 2-port foreign exchange station, direct inward dial, foreign exchange office and a basic rate interface. The device is capable for online insertion and removal without powering off the router. It supports both ground and loop start modes and is equipped with an overload protection.